The present invention relates to a system for controlling ground movement on airfields. The control which is exerted is applied chiefly to aircraft maneuvering on runways and access ways from their parking area to take-off or conversely from landing to a parking area, but it is understood that other moving vehicles using these routes may likewise be controlled by the system.
The control system is intended to detect and transmit information required for supervising the routes along which movement takes place, to allow significant variables to be calculated on the basis of this information, and to allow these variables to be processed and then transmitted for use, which transmission may take place on the one hand to a display or indicator panel and on the other hand to the moving vehicles being controlled to allow orders and information to be displayed for the pilots.
The system is intended to assist in guiding aircraft on runways so that their movement takes place along the centerline of the runway, which may be a problem in the case of aircraft of wide track or span. It also enables control to be exerted on the traffic resulting from the various vehicles which are moving about on the routes, runways and access ways of the airfield which are being monitored, and thus any possibility of collision to be prevented, while at the same time permitting a high density of traffic as a result of this control.
It is known to determine the path of aircraft with respect to the ground during the taking off or the landing periods, by utilizing a multiplicity of detection elements disposed at known intervals from one another and extending in a direction perpendicular to that of the track, each detection element comprising a flexible strip and detecting circuits at each end to convert to electric signals the pressure variations caused as the aircraft passes over the strip. The phase of the detected signals are compared to measure the lateral deviation of the aircraft. Computing means are further provided to compute other parameters, in particular, the speed of the aircraft.